It was a sad end to one of the most encouraging weeks of Henman's career, especially after he had taken the first set playing the kind of controlled and varied tennis that saw him beat Franco Squillari and Mariano Puerta earlier in the week. But a careless service game at the start of the second set turned the tide irrevocably Zabaleta's way.
The most frustrating thing for Henman was that he pulled back a 1-3 deficit in the final set and led 4-3, but from then on he lost 12 of the next 13 points as his forehand broke down and he presented the victory to Zabaleta. "I just wasn't consistent enough," Henman said, "and that's something I just have to learn on this surface."
The result should not detract from what could be one of the pivotal weeks of Henman's career, in which his long-running battle to master the one surface he is still vulnerable on has borne fruit. He finally seems comfortable with the unique movement and footwork that clay requires, sliding confidently and gracefully to the ball, and judging when to attack and when to trade punches from the baseline.
As such he was upbeat about his chances at next week's Italian Open and the French Open which begins a fortnight on Monday in Paris, both events known for their quicker clay. "I came here knowing I was playing good tennis, but to then convert that to results in a big tournament like this gives me a lot of added self-belief, and that'll help me in Rome."
Henman's defeat ends Carlos Moya's chances of returning to No 1 in the rankings this week. Moya, who said he played better than he had played in winning at Roland Garros last year in his stunning 6-0, 6-2 victory over Gustavo Kuerten yesterday, needed to win the German Open and pick up enough bonus points on the way. Only Henman, the world No 7, was ranked high enough to have given him the 104 points he needs.
"I was a bit nervous and I was very concentrated the whole match," said Moya, of his exceptional performance. "If I had picked a tournament to beat [Kuerten] on clay, it wouldn't have been here."
Moya's return to the No 1 slot - perhaps after next week's Italian Open - would be a relief for the ATP Tour, which is embarrassed at having a new No 1 Yevgeny Kafelnikov who has not only lost six first rounds this year but has been accused of not trying and running down some of the Tour's top events.
Moya will meet another former world No 1, the Chilean Marcelo Rios, in the semi-finals today. Rios, the fourth seed, beat Tommy Haas 6-4, 6-4, ending the local favourite's hopes of becoming the first German to win the tournament since Michael Stich in 1993.Reuse content